alt Hacker NewsA lot of walls were open after a kitchen fire. Electrician was redoing a lot of knob and tube and other older wiring. I had previously had a limited amount of DIY wireless switching (originally X10 but then a couple of voice-controlled switches) but basically everything was being redone anyway. And I basically just now have some dimmers and a simple programmable thermostat I haven't even programmed.
The parent point was that it's silly not to have a smart house (whatever that means exactly) and I disagree. It may make sense to do selectively rather than get an electrician in unless you have some other reason to do so.
As for threshold probably all the safety stuff: power metering, water leak sensors, smoke alarm monitoring. Then all the energy related stuff - heating, hot water controls - if you are on TOU pays itself in months. Then it's smart entry - probably one thing that you can actually experience and it's the best.